w
w
ap
eP
m
e
tr
.X
w
om
.c
s
er
UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*0063574818*
5090/02
BIOLOGY
Paper 2 Theory
May/June 2007
1 hour 45 minutes
Candidates answer Section A on the Question Paper
Additional Materials:
Answer Booklet/Paper
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Sections A
Answer all questions.
Write your answers in the spaces provided on the Question Paper.
Section B
Answer all the questions including questions 6, 7 and 8 Either or 8 Or.
Write your answers on the separate Answer Paper provided.
Write an E (for Either) or an O (for Or) next to the number 8 in the grid below to indicate which question you
have answered.
You are advised to spend no longer than one hour on Section A and no longer than
45 minutes on Section B.
At the end of the examination fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part
question.
For Examiner’s Use
Section A
Section B
6
7
8
Total
This document consists of 13 printed pages and 3 blank pages.
SP (FF/CG) T25825/6
© UCLES 2007
[Turn over
For
Examiner’s
Use
2
Section A
Answer all the questions in this section.
Write your answers in the spaces provided.
1
Fig. 1.1 shows sections through two different flowers, A and B, that are found on the same
plant. One flower is male, the other is female.
C
C
flower A
flower B
Fig. 1.1
(a) Identify C on Fig. 1.1 .................................................................................................... [1]
(b) State which flower is the male flower and give a reason.
flower .......................................................
reason ..........................................................................................................................[1]
© UCLES 2007
5090/02/M/J/07
3
(c) (i)
State the method of pollination in this plant and give two reasons for your answer.
For
Examiner’s
Use
method of pollination .................................................................................................
reason 1. .................................................................................................................
2. .............................................................................................................[3]
(ii)
State two other possible features, not visible on Fig. 1.1, that are likely to be present
in these flowers.
1. ..............................................................................................................................
2. ..........................................................................................................................[2]
(d) In some species, plants with only male flowers occur while other plants have only female
flowers. Explain the advantages of this to the species.
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
......................................................................................................................................[3]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
[Turn over
4
2
Fig. 2.1 shows two microscopic structures that are adapted for absorption, one from an
animal and the other from a plant. The structures are not drawn to the same magnification.
structure D
structure E
Fig. 2.1
(a) State one feature that these two structures have in common that helps them to carry out
their function.
..........................................................................................................................................
......................................................................................................................................[1]
(b) Identify each structure and, for each one, name two chemical substances that are
absorbed by it.
structure D: name
........................................................................................................
chemical substance 1. ....................................................................................................
2. ....................................................................................................
structure E: name
........................................................................................................
chemical substance 1. ....................................................................................................
2. ................................................................................................[6]
© UCLES 2007
5090/02/M/J/07
For
Examiner’s
Use
5
(c) (i)
Structure E in Fig. 2.1 is a single cell. Draw in and label, on Fig. 2.1, a feature that
helps the cell to carry out absorption.
[1]
(ii)
Explain how the feature you have drawn and labelled helps the cell to carry out
absorption.
For
Examiner’s
Use
..................................................................................................................................
..................................................................................................................................
..................................................................................................................................
..................................................................................................................................
..............................................................................................................................[2]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
[Turn over
6
3
When a strip of filter paper is soaked in cobalt chloride solution, it is pink when damp and
turns blue when dry.
Fig. 3.1 shows strips of dry cobalt chloride paper on the upper and lower surfaces of a leaf,
pressed between dry glass slides.
elastic band
cobalt chloride
paper
cobalt
chloride
paper
glass slide
leaf
leaf, slides and cobalt chloride
paper shown in section
leaf attached
to plant
glass slides
Fig. 3.1
A student used this method to investigate the time taken for strips of cobalt chloride paper
to turn from blue to pink. The experiment was performed five times. The results are shown in
Table 3.2.
Table 3.2
experiment
number
© UCLES 2007
time (in minutes) taken for paper to change from blue to pink
upper surface
lower surface
1
10
3
2
13
4
3
4
3
4
11
4
5
12
3
5090/02/M/J/07
For
Examiner’s
Use
7
(a) (i)
State the most likely conclusion that could be drawn from the results of experiments
1, 2, 4 and 5.
For
Examiner’s
Use
..................................................................................................................................
..............................................................................................................................[1]
(ii)
Suggest an explanation for the results of these experiments
for the upper surface of the leaf,
..................................................................................................................................
..................................................................................................................................
..................................................................................................................................
for the lower surface of the leaf.
..................................................................................................................................
..................................................................................................................................
..............................................................................................................................[4]
(b) Suggest two possible reasons for the result obtained for the strip attached to the upper
surface of the leaf in experiment 3.
1. .....................................................................................................................................
2. .................................................................................................................................[2]
(c) Suggest how the student could improve the reliability of this experiment.
..........................................................................................................................................
..........................................................................................................................................
......................................................................................................................................[1]
(d) Suggest how the student could show that the concentration of water vapour coming out
of a leaf is greater than its concentration in the atmosphere.
..........................................................................................................................................
..........................................................................................................................................
......................................................................................................................................[2]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
[Turn over
8
4
Microorganisms can be grown in the laboratory on agar (a jelly-like medium) in a Petri dish.
Nutrients required by the microorganisms are added to the agar.
(a) Name a nutrient that should be added to ensure the maximum rates of
(i)
respiration ................................................................................................................
(ii)
growth ................................................................................................................... [2]
(b) Respiration and growth are enzyme-controlled processes.
A student is provided with a Petri dish containing agar with the optimum concentration of
nutrients. Explain how the student could speed up the rate of growth of microorganisms
growing in this Petri dish.
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
......................................................................................................................................[2]
Fig. 4.1 shows the stages in an experiment to show the effect of different antibiotics on
microorganisms.
layer of microorganisms on surface
clear areas
Petri dish
I
G
H
F
nutrient agar jelly
I
G
H
J
J
F
discs of filter paper
soaked in different antibiotics
immediately after discs have been
placed on the layer of microorganisms
24 hours later
Fig. 4.1
The microorganisms originally came from the throat of a person suffering from a throat
infection.
© UCLES 2007
5090/02/M/J/07
For
Examiner’s
Use
For
Examiner’s
Use
9
(c) Using the information in Fig. 4.1,
(i)
identify by letter the antibiotic which might be best for treating the infection,
......................................
(ii)
[1]
state which type of microorganism was probably causing the throat infection and
give a reason for your answer.
type of microorganism ..............................................................................................
reason ...................................................................................................................[2]
(d) Antibiotic F used to be the most effective in treating the infection. Suggest and explain
why it has become less effective.
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
......................................................................................................................................[3]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
[Turn over
10
5
Fig. 5.1 shows some food just before it enters the stomach and the same food as it leaves
the stomach four hours later.
K
N
M
L
Fig. 5.1
(a) On Fig. 5.1, label structures K and L.
[2]
(b) The food consisted solely of meat and potatoes. By placing ticks ( ✓ ) in the appropriate
boxes in Table 5.2, show how the major components of the food compare at positions M
and N.
Table 5.2
more at M
than at N
less at M
than at N
almost the same
at M and N
starch
protein
fibre
[3]
© UCLES 2007
5090/02/M/J/07
For
Examiner’s
Use
For
Examiner’s
Use
11
Fig. 5.3 shows the same food at O, and 24 hours later, at P.
O
P
Fig. 5.3
(c) (i)
Explain what has happened to the protein between O and P.
..................................................................................................................................
..................................................................................................................................
..............................................................................................................................[2]
(ii)
Name the region of the alimentary canal which will contain fibre in the highest
proportion and give reasons for your answer.
region of alimentary canal .........................................................................................
reasons ....................................................................................................................
..................................................................................................................................
..................................................................................................................................
..............................................................................................................................[3]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
[Turn over
12
Section B
Answer all the questions including questions 6, 7 and 8 Either or 8 Or.
Write your answers on the separate answer paper provided.
6
Fig. 6.1 shows parts of some natural cycles in the environment.
S
R
R
Q
Q
Fig. 6.1
(a) With reference to the carbon and nitrogen cycles, explain what is happening at Q and R.
[7]
(b) Identify two gases that may be released at S and describe the possible harmful effects they
may have on the environment.
[3]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
13
7
(a) With reference to the circulatory system, name an example of each of the following:
(i)
a cell,
(ii)
a tissue and
(iii)
an organ.
[3]
(b) Name the main blood vessels carrying blood to and from the liver and describe any differences
that there may be between the composition of the blood as it enters and leaves the liver. [7]
[Total: 10]
Question 8 is in the form of an Either/Or question. Answer only question 8 Either or question 8 Or.
8
Either
(a) Define a drug.
[2]
(b) Explain the effects of the abuse of:
(i)
alcohol, and
(ii)
heroin.
[8]
[Total: 10]
8
Or
Explain why smoking is no longer regarded as
(a) advisable for the maintenance of good health,
[8]
(b) socially acceptable.
[2]
[Total: 10]
© UCLES 2007
5090/02/M/J/07
14
BLANK PAGE
5090/02/M/J/07
15
BLANK PAGE
5090/02/M/J/07
16
BLANK PAGE
Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
5090/02/M/J/07